2012-04-24JOSEPH BAKER:I used 1 1/2", but measured the tank nipple with a caliper. Order an extra foot, for bends and ease of working. Then cut with a hack saw, and snip the wire, and vacuum the i/s before connecting.

2012-05-01GARY S SNYDER:1 1/2 inch dia by 7ft long. old hose was disolving because of ethanol

2012-05-02TIM FIVES:You'll need to measure from your the point where you fill on your boat to the intake on the tank, most filler hose is the same diameter 1 1/2 inch.
Tim